Possible compiler bug in Swift 5.7, compactMap disambiguation?

[lukeredpath]

I've run into an issue in my project where the Swift compiler seems to be favouring the Parser.compactMap method on a [String] over the foundation compactMap in some scenarios, particularly if there is some other compiler error within the compact map closure. I've managed to reproduce this with some examples in the Parsing playground here which should hopefully demonstrate the problem.

https://github.com/lukeredpath/swift-parsing/blob/lukeredpath/swift-parser-bug/Parsing.playground/Contents.swift

It's as if the @disfavoredOverload annotation is not being respected, but I can't see why the compiler is even getting confused given I'm being explicit about the return type, and Parser.compactMap returns a Parsers.CompactMap type, not a [Value].

Has anyone run into something similar? This feels like a compiler bug.